Re using calibration frames??

[Jbunky86]

Hi everybody
Just wondering if darks, flats and bias frames can be used for multiple sessions?

Or is it optimal to do a new set of calibration frames for each session?

Thanks in advance

[RickS]

Bias frames are generally good for some time. Darks can also be reused if you have a temperature controlled camera. Flats are normally redone each session because they are most likely to change (new dust spots, differences in illumination because of camera rotation, etc.)

Cheers,
Rick.

[allan gould]

Rick is correct but sometimes I mess up my flats or they don't correct properly and I have used those from the previous night but only as I hadn't changed the filter ie only used the luminance from night to night and the same focus. So you can get away with it but only rarely. Darks and biases cam be reused for about a month as long as nothing really changes.

[Paul Haese]

If your setup does not get moved or diassembled then you can use the same flats for months on end. That is what I do and i don't have any calibration problems.

[gregbradley]

Same.

I only take new flats if the old ones aren't working well or I have moved the camera orientation.

I always test out the first download to make sure all is well.

Greg.

[Jbunky86]

Great advice thanks guys

Cheers
Jason

[Terry B]

My camera stays on the scope. I use darks for about a year and have never made new bias framed. I made a new set and tested it by subtracting the new one from the old one. There was no difference.
Flats last til I take the camera off the scope. You do need different flats for each filter though.

[silv]

learned this the hard way the other night :lol: